Abstract In this article I explore the psychocultural underpinnings of authenticity as a signature feature of late modernity. I examine the self-narratives of baby boomers in the United States, the generation that came of age under emerging postmodern conditions. The data point to shared emotional dynamics that not only provide a culture of authenticity with a strong motivational foundation but also inform the subjective experiences of modern rationality. The baby boomers, from their own bodily feelings and emotions, present a poignant critique of modern rationality. This antimodernist stance leads them to the postmodern conception and practice of selfhood, at the heart of which lies authenticity. The postmodern self takes shape by way of antimodernism, but remains within the modernist tradition of self-transformation. Throughout the paradoxical contour of inner experiences of modernity is found a remarkable cultural and generational continuity.